Conventionally, when a disc has a defective portion into which a signal or information cannot be recorded, if the information to be recorded is information such as text data, then a substitution track is provided as a substitute for the defective portion and the information to be written into the defective portion is written into the substitution track. During reproduction, when the defective portion is read out, a search operation is performed using the substitution track so that the recording and reproduction can be executed even when the disc has the unrecordable defective portion. Therefore, a disc having a defective portion amounting to less than a predetermined portion of the disc need not be discarded as inferior goods. Thus, the production efficiency for the discs can be enhanced.
When the record information is a video signal, however, the recorded images must be successive or continuous during reproduction. For this reason, during recording, a research operation is executed to thereby write the video signal into the substitution track while, during reproduction, if the video signal is read out by means of a search operation, then images occurring during the search operation are discontinuous. The present invention was motivated by a desire to overcome this problem.